Continuous cleanup sluice box and concentrator



Nov. 22, 1949 s. OVERPECK 2,488,540

cqmmuous CLEANUP SLUICE BOX AND CONCENTRATOR Filed Sept. 14, 1946 INVENTOR- Lem 5. Over neck.

HTTOHNEY. I

Patented Nov. 22, 1949 CONTINUOUS CLEANUP SLUICE BOX AND CONCENTRATOR Lem S. overpeck, Los Angeles, Calif.

Application September 14, 1946, Serial No. 697,088

6 Claims.

This invention relates to a novel continuous cleanup sluice box and concentrator, which is used primarily in placer mining to separate and impound precious and non-precious metals and minerals from gangue material. My device, however, can also be used on dredges and in gravel plants.

The prime object of my invention is to provide a novel device of the character stated, in

which a means is provided of securing a continuous cleanup, that is, a continuous withdrawal of the concentrates or valuable metallic particles.

A further object is to provide a novel arrangement of the riffles in the box, whereby said rifiles are kept free and deliver the valuable particles through a longitudinal slot, into a launder positioned below the sluice box, these valuable particles being then collected from the launder.

Still another object is to provide a novel separation means in the launder, adjacent the outlet end thereof, whereby a number of concentrates can be simultaneously withdrawn from the material progressing through the launder.

More particularly, I provide a means of separating the particles of high specific gravity, of medium specific and low specific gravity. It is understood that the specific gravities of the specific particles are only relative.

A feature of my invention is'the elimination of the carrying off of Values by clay balls and other means of stealing in the sluice box.

Another feature of my invention is to provide a sluice box in which both precious and nonprecious metals can be recovered in one operation.

I also provide a means of immediately arranging the values and withdrawing them so that subsequent losses are eliminated.

Still another feature of my invention is the bottom of the sluice box I.

Referring more particularly to the drawing, the numeral i indicates a sluice box of suitable width and length. At the head of the box, a suitable screen or grizzly (not shown), is provided to reject coarse material, boulders, etc. Within the box I, I provide a series of spaced riflles 2. These rifiles may be in various shapes such as plain, Z, I, or channel shaped as desired. The riffies are arranged substantially in pairs and are inclined in the direction of flow of the material, through the box.

The material flows in the direction shown by the arrow 3 in Figure 1. The riffles 2 are mounted on a false bottom 4 and 'a longitudinal slot 5 is provided in the false bottom 4, this slot extending substantially the length of the box I, however, it terminates approximately at the sump at the lower end of the grizzly, which will be subsequently described.

The rifiles 2 direct the concentrates towards the center of the sluice box and these values then drop through the slots 5 and into the launder 8.

The launder is substantially a rectangular fiume or trough, and may be formed as a part of the A spiral conveyor 1 is mounted in the launder and the conveyor is suitably driven from a source of power not shown, for example, through the sprocket 8.

A pair of water pipes 9 are provided in the launder and extend longitudinally therethrough, these pipes spraying water inwardly to assist in carrying the values along in the launder. Adjacent the outlet end of the launder, I provide a sump I0. This sump will have tapering sides substantially as shown and a transverse baffle I I, the upper end of the bafile is bent forwardly as shown at l2, and thus extends into the stream of material flowing through the launder. The heavier values, i. e., those of high specific gravity, will be moving along the bottom of the launder, and-thus will be caught by the baflle and deflected downwardly into the sump.

A withdrawal pipe I3 is provided in the bottom of the sump I0, and the values of high specific gravity are collected in this pipe. A water jet I4 projects upwardly in the pipe I3 and water flowing through this pipe or jet, will agitate this material, and the values of lesser specific gravity will flow upwardly and will be deflected downwardly by a second transverse baflie I5. These values which I will term mediums specific gravity are then withdrawn at the throat I6. It is to be noted that the wall of the sump I0 is curved, as shown at IT, thus promoting the flow of values to the outlet throat l6.

The middlings or values of lesser specific gravity flow over the baffles ll|5, and are collected at the outlet l8. It will be evident from the foregoing that I continuously collect values of different specific gravities and accomplish this continuously While the sluice box is in operation. The slot 5 terminates approximately at the inlet of the sump ID, the reason for this being that it is desirable that all values shall drop into the launder before the sump is reached, otherwise, some of the values might pass over the bafile l I.

Having described my invention, I claim:

1. A continuous cleanup sluice box andconcentrator comprising a floor, said floor having a longitudinal slot therein, a launder positioned below said slot and adapted to receive values dropping through said slot, a plurality of inclined riflles on the floor, said riffles being inclined towards said slot, and a sump at the outlet end of said launder, said sump receiving the values from the launder, and a spiral conveyor in said launder means to rotate said conveyor, whereby the values are assisted in their movement through the launder.

2. A continuous cleanup sluice box and concentrator comprising a floor, said floor having a longitudinal slot therein, a launder positioned below said slot and adapted to receive values dropping through said slot, a plurality of inclined riifles on the floor, said rifiles being inclined towards said slot, and a sump at the outlet end of said launder, said sump receiving the values from the launder, an outlet pipe in the bottom of said sump, a transverse bafile in said sump, said baffle projecting upwardly into the stream of material flowing through the launder.

3. A continuous cleanup sluice box and. concentrator comprising a floor, said floor having a longitudinal slot therein, a launder positioned below said slot and adapted to receive values dropping through said slot, a plurality of inclined rifiles on the floor, said rifiles being inclined towards said slot, and a sump at the outlet end of said launder, said sump receiving the values from the launder, an outlet pipe in the bottom of said sump, a transverse baffle in said sump, said bafile projecting upwardly into the stream of material flowing through the launder, a second horizontal transversely extending bafile in the sump, said sump having an outlet throat below said second bafile, and a main outlet above said second bafile.

4. A continuous cleanup sluice box and concentrator comprising a floor, said floor having a longitudinal slot therein, a launder positioned below said slot and adapted to receive values dropping through said slot, a plurality of inclined riilles on the floor, said riflles being inclined towards said slot, and a sump at the outlet end of said launder, said sump receiving the values from the launder, an outlet pipe in the bottom of said sump, a transverse bathe in said sump, said baffle projecting upwardly into the stream of material flowingthrough the launder, and a water jet in the sump, said water jet being directed upwardly.

5. A continuous cleanup sluice box and concentrator comprising a floor, said floor having a longitudinal slot therein, a launder positioned below said slot and adapted to receive values dropping through said slot, a plurality of inclined rifiles on the floor, said riffles being inclined towards said slot, and a sump at the outlet end of said launder, said sump receiving the values from the launder,

an'outlet'pipe in the bottom of said sump, a transverse bafile in said sump, said baflle projecting upwardly into the stream of material flowing through the launder, a second horizontal transversely extending bafile in the sump, said sump having an outlet throat below said second battle, and a main outlet above said second bafile, and a water jet in said sump, said water jet being directed upwardly.

6. A continuous cleanup sluice box and concentrator comprising a floor, said floor having a longitudinal slot therein, a launder positioned below said slot and adapted to receive values dropping through said slot, a plurality of inclined rifiles on the floor, said riilles being inclined toward said slot, a sump positioned at the outward end of said launder, said sump receiving the values from the launder, an outlet pipe in the bottom of said sump, a transverse baflle mounted in said sump and spaced from the wall of said sump whereby a passage is provided between the baiile and the wall of the sump, said ba'file projecting upwardly to the stream of material flowing through the launder.

LEM S. OVERPECK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,218,977 Burnhart Mar, 13, 1917 1,409,385 McDougall Mar. 14, 1922 

